function s1_generate_a_series_of_files(){
	for i in {1..100}; do
		printf "%s" $i > /tmp/new_file$i
	done
}

function s2_list_4_files_in_long_format_about_account_and_group(){	
	ls -l /etc/{passwd,shadow,group,gshadow} | sort -d
}

function s3_find_items_related_to_given_username(){
	grep -h "^$1:" /etc/{passwd,shadow} | sort -d
}

function s4_find_items_related_to_given_group_name(){
	grep -h "^$1:" /etc/group /etc/gshadow | sort -d
}

function s5_create_groups_for_given_group_names(){
	sudo groupadd -f rnd && sudo groupadd -f itoperation
}

function s6_create_users_and_set_their_group_as_required(){
	sudo useradd -m -s /bin/bash -G rnd adam
	sudo useradd -m -s /bin/bash -G rnd bob
	sudo useradd -m -s /bin/bash -G itoperation calvin
	sudo useradd -m -s /bin/bash -G itoperation david
	sudo useradd -m -s /bin/bash -G rnd edward
}

function s7_change_users_shell(){
	sudo usermod -s /usr/bin/sh adam 
       	sudo usermod -s /usr/bin/sh edward
}

function s8_set_password_change_policy(){
	passwd -m 10 -M 60 -W 10 adam
	passwd -m 10 -M 60 -W 10 bob
	passwd -m 10 -M 60 -W 10 david
	passwd -m 10 -M 60 -W 10 calvin
	passwd -m 10 -M 60 -W 10 edward
}

function s9_set_password_for_five_users(){
	echo "adam:$1" | sudo chpasswd
	echo "bob:$2" | sudo chpasswd
	echo "calvin:$3" | sudo chpasswd
	echo "david:$4" | sudo chpasswd
	echo "edward:$5" | sudo chapsswd
}

function s10_lock_bobs_password(){
	sudo usermod -L bob 
}

function s11_include_adam_into_wheel_group(){
	sudo grouadd -f wheel
	sudo usermod -aG wheel adam

}

function s12_change_files_permission(){

	for i in {1..33}; do
		chmod 640 /tmp/new_file$(($i*3))
	done

}
